Furnace door or the like



R- B. GROETZINGER FURNACE DOOR OR THE LIKE April 3, 1951 2 Sheeis-Shee't 1 Filed April 1, 1944 Ray/77004 6. Groefz/nger Nflaa April 3, 1951 R. B. GROETZINGER' FURNACE DOOR OR THE LIKE 2 Sheets-Sheet 2 Filed April 1, 1944 INVENTOR A ay/7700029. Groefzvhyer v AM M NM Patented Apr. 3, 1951 Raymond B. Groetzinger, Hittsburgh,,l?a.,ass ignor tocBlaw'Knox Company;TPittsburh,"TPa., a.

corporation ofNew Jersey :ApplicMionApriLl, 1944;SeriaI-:l Io. 529}059 f3 Claims. CURE-.193)

$33 .1 invention relates .to a .furnace door and, :in :narticul r, :to ca ..water-.coo1e,d :door .having a :refractorwlin-ing or protective layer over the ,inneniacethereof.

,The p1acin g .of .the refractory lining ,in such dents islfrequently done by the purchaser and not .necessarilyghy .the manufacturer of the hollow metal paneltor..of the refractory, these, being ,nsually furnishedseparately. The metal panel .may V1be;,reline,d.-with refractory .bysthe purchaser, ,or thelining maygbe patehed-or repaired, the

:panel being-in the nature of apermanent struc- -1i1 Ze rand .theylining, although in my invention .havi.n g a much longer .life than fin. any other ..doors,;is subjecttodeterioration in :use and may ultimately Joe replaced withanew one. My in- .vention relates particularly to ,an improved hollow metaLdoo-r panel as .an .articleofmanu- .facture. I

It. has been-quite general heretoforeto provide aiurnace doors, such .as those used .for open- .hearth. furnaces, comprising. a hollow metal .panjel arranged-for .water. coolingand .a layerof refractory material extending over one face thereof, with .heat-conductingmeans,such as metal studs, .g.projecting';from the inner wall 'D'f'f'the" panel" the lining, to absorb heat from the"1ining"and -.also.to anchor it mechanically to themetal-panel -..,or}.bak .of the door. This prior"construction is described in. Fuchs Patent 23255945, 'whichalso discloses the ,us'ing of studs or shelves o'f*a con- ;ductive' refractory "instead of "metal studs. "Whether the studs are 'ofimeta'l -or of refractory material th'ey cool thefliningto-'alimited extent only; and, "when' the studs "orother *supports -;be.come exposeddue to the face-of the lining being gradually. consumedithe supportsare themselves damaged and must" be replaeedwhen-a newlining is applied. The object of this invention is todm- =proveupon the "prior construction referred to "above and to provide a longer-li'fe for thelininglsy maintaining. it at considerably lower ttemp erature and e150 to "provide a permanentsanchorage :for

the lining to the back-of the door-which can eb'e 'rline'd 'indefinitely with plastic refractory.

Ina-preferred embodiment, my invention-.-comprises-a furnace door or the like composed of a water-cooled panel or back provided with a ,secured to the inner wall ofthe doorpanel'and communicating Withthe interior thereof. "The straight pipes are secured at one end only; the

-. b.ent pipes are secured aVbothen'ds. *By "this,

:&2 construction the :cooling water supplied to the ;interiorvof2the,-.door panel -.or ,bach-flowslintoflthie ;.-pipe lengths; therehyservingr-both toabsoroheat flromgthe.lining -and. to protect the pipe lengths .5 wfro'm burning when exposedato the furnace. gases. jilihe gpipe; lengths .also .serve. tolholdithe .liningIin place on the-door. whe pipezlengths, .or. at least meof :;them,;-.n ay.=be-.disposed titan-angle to the eri-zontal so.-;that grayity circulation of-mater therethrough is obtained.

Eurther ,detailszandinovekfeatures of the intenetion ,willghe eigplainedrduring .thefiollowinecomplete description f the .preferred .embodiment ndewmgdificationiughich.referto theaccornpanyaing drawings. -ln thedrawings, v

,iFigure .1 is an eleyation of the .interior .faee .-,of-1one: form 'Of'rdOQPWithzthB lining omittedi from "all but a: port her o eFigure is, a yertical seetion ;taken along the -p1aneor lin re IQ rEiQuBeI;

,.#Figur.e...2A; ;is apartial sectional view taken zalongitheline 0f..1.IA- IIA.1 'f Figure 1-;

. glF'igure -3 .;is..;a yieW;.:simi1-ar t JFigure l-showing ainodifi a ioman FigureszA and .5; are ftransverseesections ta-ken ralon zthe ;p1ane aof.;l 1es.;I =IV and v-av. 'rrespe t velycoffliaure .fleierringvin-detail tothe drawings and,;.for;the pr sent, t -Figures =1 andz, th wem ed m n inf 30 "my invention;therenllustrated is-a urn-aee; -;door comprising a double-walled metal: anchor-hack L0 shavin .1 inward y extending.marginalifiange g-M za-lin-ing lor; prote ctive;; laye i201?v refract o1 'y :material substantially filling ,the space defined-.h y..,tl 1epfiangeJJ. Thedoor hasalifting eyed 3 and lugs A14 to :whichoperating linkszmay aloe pivoted. :An; inlet connection t5 ,fortcoolin'g ewaateriha aa pipe-tfi extending downwardly there- .Irom throng-lithe; panel twat one side to .apoin't o .near .the bottom while :an outlet connection. if]

.i ;,located,.at vtheitop .of .thepanel on the other lside. -.C1ean-.o.ut holeslmin .thesides of the ;.door .near ,the .bottomare provided with removable Qplugs. i5.

icated from plate,lb,eing..composed .o'f .spacedwafll's cannectedhy staybolts. 19. .QA wicket or peep-hole 'llljinthetormofyalength of tube extends through the doorenear the bottom. A sleeve iZl havin g 5o :a .diameter ,s0n1eu7. hat greater than that of jthe wicketprovidesa jacket 'for cooling Walter: around the inner enld of'theilatter.

A plurality f pipeflengths220, 2'213; 22c,,antl "22171761" yoke orwashapeare disposedjonlthe inner face :of the panel "I'D *wit-hin the tspaee "defined *by ,The .d0or .back .or.., panel 4.0 .is .preferably .fabri 3 the flange II, having their ends secured as by welding to said face at spaced points thereon at which holes 23 are formed whereby the pipe lengths communicate at each end with the interior of the panel ll]. As shown in Figure 1, the pipe lengths are disposed at various angles to the horizontal, the pipe lengths 22a and 22b, for example, being at an angle of about 50, the pipes 220 at an angle of 90 while the pipes 22d are substantially horizontal. As shown in Figure 2, the pipe lengths are wholly embedded in the lining l2 which is substantially flush with the inner face of the flange ll.

Extending inwardly from additional holes 23 in the side flanges II are a plurality of straight pipes or hollow studs 24, opening into the body of the interior of the door panel and closed at their outer ends. On the upper and lower flanges II and around the greater part of the circumference of. sleeve 2| are provided and secured at other holes 23 a plurality of L-shaped pipes 25, 'a substantially horizontal arm of which enters and is welded to the inner face of panel 10 at other holes 23 providing an opening into the body of the panel, the other arm communicating with the interior of the flanges of H and 20 (see "Figs. 2 and 2A). Extending diagonally from the lower portion of 2| into lower flange H are two straight pipes 26, spaced from the back of the door.

' The pipe lengths 22a, 22?), etc., 24, 25 and 26 perform two functions. In the first place, they serve mechanically to anchor the lining l2 tothe door back or' panel 10 and prevent falling out of portions thereof even should the lining become tion, the presence of water in the pipe lengths at points on the exposed surface thereof where slight spalling occ.urred. V

=cools them below the temperature at which they become burned or consumed after thelining, near fthe' end of its life, no longer covers them completely, so that the door may be relined with refractory without having first to replace the'anchorage structure. r The pipes are all disposed so as to provide an outlet for generated steam into the body of the 'door without trapping the steam within the pipes. The studs 24 all open above or at the same level as the highest portion of their interior. The Ls 25 provide steam outlets at their highest points. The 'fyokes 22a, 22b, and 22a provide an outlet above ,the point of water inlet, while in yokes 22d steam may escape at either end without being trapped in :'the yoke. Circulation of water through the yokes by thermo siphonic action is provided in pipe lengths 22a, 22b, 22c and 25-, which make up the majority of the anchorages for the lining. This ,increases somewhat the effectiveness of the cooling of the lining. In the other pipe lengths, the steam bubbles set up circulation; and the arrangement provides, at least, that water will enter and cool the yokes as fast as steam is generated.

A modified form ofdoor illustrated in Figures 3 through is generally similar to that described above. It comprises a double-walled panel or Lback 30 having an inwardly extending marginal ,fiange 3i and a lining or protective layer of refractory material 32 applied thereto. In the lining are embedded pipe lengths 33 and 34 having their ends secured to the inner wall of the panel and communicating with the interior thereof. In general, the modified form of door differs from the form first described in that the panel 30 is convex exteriorly instead of substantially flat as in the case of the door in Figures 1 and 2. The pipe lengths 33, furthermore, extend substantially the full width of the door and are arranged at a small angle to the horizontal. The pipe lengths 34 are of such length as to be accommodated between the sides of the door and the wicket 35 which is generally similar to that shown at 28. It will be apparent that the pipe lengths 33 and 34 perform the same function as the pipe lengths 22a, 22b, etc., viz., cooling the lining 32 by permitting the circulation therethrough of cooling water supplied ing than the heat-conducting studs welded to the inner face of the lining used heretofore. The danger of burning the lining or of sagging thereof as a result of overheating is entirely avoided. The pipe lengths also have a more effective mechanical interlock with the lining than the metal studs and the possibility of any portion of the lining fallingout is practically eliminated even though the lining as a whole should become badly cracked. The cooling pipes, being wholly embedded in the lining, are protected from the high temperature existing on the inside of the furnace.

Doors constructed in accordance with the invention, when'installed on an open-hearth furnace, have. demonstrated their ability to withstand a number of heats much greater than that of which the best doors of previous construction were capable, without requiring any maintenance beyond the occasional application of a small amount of lining material as may be necessary Although I have illustrated and described but two forms of the invention, it will be recognized that changes in the details of the construction illustrated may be made without departing from the spirit of the invention or the scope of the appended claims. The metal panel or back of the door, for example, instead of being continuous, may be of the grid type shown in Williams Patent 1,690,606, and the word panel as used in the claims is intended to include such type.

I claim: 1. In a water-cooled hollow metal furnace door for an open-hearth furnace or the like, a

hollow double-walled panel having a generally vertical inner wall and a generally vertical "back between which a relatively large volume of cooling water is adapted to be circulated, said panel further having a hollow peripheral inwardly extending marginal flange defining with the inner face of said inner wall a refractory lining space of a predetermined thickness adapted ends thereof opening into the interior of said hollow double-Walled panel, said pipe lengths fur- Y lengths interlock, anchor and cool said refractory lining during the service thereof.

2. In a water-cooled hollow metal furnace door for an open-hearth furnace or the like, a hollow double-walled panel having a generally vertical inner wall and a generally vertical back between which a relatively large volume of cooling water is adapted to be circulated, said panel further having a hollow peripheral inwardly extending marginal flange defining with the inner face of said inner wall a refractory lining space of a predetermined thickness adapted to be filled with a plastic refractory lining, a plurality of relatively short generally U-shaped cooling water pipe lengths in a predetermined pattern connected to said inner wall and extending inwardly thereof to lie entirely within said lining space, substantially all of said pipe lengths lying in planes generally normal to said inner wall, substantially all of said pipe lengths further being at an angle to the horizontal and having the respective ends thereof opening directly into the interior of said hollow double-walled panel, said pipe lengths further extending relatively close to the plane defined by the face of said flange, whereby said pipe lengths interlock, anchor and cool said refractory lining during the service thereof.

3. In a water-cooled hollow metal furnace door for an open-hearth furnace or the like, a hollow double-walled panel having a generally vertical inner wall and a generally vertical back between which a relatively large volume of cooling Water is adapted to be circulated, said panel further having a hollow peripheral inwardl extending marginal flange defining with the inner face of said inner wall a refractory lining space of a predetermined thickness adapted to be filled with a plastic refractory lining, a plurality of relatively short generally U-shaped cooling water pipe lengths in a predetermined pattern positioned at ther having the respective ends thereof opening' into the interior of said hollow double-walled panel, said pipe lengths further extending relatively close to the plane defined by the face of said flange, whereby said pipe lengths form yokes which interlock and anchor said refractory lining and respectively permit cooling water to circulate therethrough by thermo-siphonic action. RAYMOND B. GROETZINGER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 312,578 Nightengale Feb. 17, 1885 387,419 Jordan Aug. 7, 1888 448,218 Fea Mar. 17, 1891 829,659 Lennon Aug. 28, 1906 1,102,668 Jones July '7, 1914 1,103,297 Knox July 14, 1914 1,667,833 Bell May 1, 1928 1,690,606 Williams Nov. 6, 1928 1,824,434 Hushour Sept. 22, 1931 1,972,593 Keenan 1- Sept. 4, 1934 2,028,160 Kerr Jan. 21, 1936 2,325,945 Fuchs Aug. 3, 1943 2,360,855 Dow et al Oct. 24, 1944 2,395,757 Peters Feb. 26, 1946 FOREIGN PATENTS Number Country Date 405,303 Great Britain Feb. 5, 1934 492,432 Germany Feb. 21, 1930 

